In many languages, it is common that some words are relating to other words. For example, in English, the verb “play” has related words such as “plays”, “playing”, “played”. The noun “element” has related words such as “elements”. The verb “entertain” is relating to its noun “entertainment” formed by adding a suffix “ment”. The verb “wonder” is relating to its adjective “wonderful” formed by adding a suffix “ful”.
Relevance means that there is some correlation between two words or phrases. For example, in English, the relevance of words may be as follows:
1. Various tense forms of a verb, e.g., past tense, continuous tense, perfect tense, third person singular form, etc. For example, for the verb “write”, the past tense is “wrote”, the continuous tense is “writing”, the perfect tense is “written”, and the third person singular form is “writes”, etc.
2. The plural form of a noun. For example, the plural form of “teacher” is “teachers”, and the plural form of “mouse” is “mice”, etc.
3. Different properties of a word. For example, the verb “entertain” is relevant to its noun form “entertainment”. The noun “wonder” is relevant to its adjective form “wonderful”. The adjective “similar” is relevant to its noun form “similarity”.
4. The comparative degree and the superlative degree of an adjective. For example, the comparative degree of the adjective “smart” is “smarter”, and the superlative degree is “smartest”.
5. The near-synonym and the antonym of a word. For example, the antonym of “advantage” is “disadvantage”, and the near-synonym of “same” is “similar”, etc.
6. The possessive form of noun. For example, the possessive form of “we” is “our”, the possessive form of “China” is “Chinese”, the possessive form of “company” is “company's”, etc.
Two or more words with relevance are related words for one another. The foregoing descriptions are merely some examples of the concept of related words. In practice, two words or phrases may be regarded as related words as long as there is relevance between them. In addition to English, such concept of related words also exists in other languages. For example, in Chinese, “I” is relevant to “my”. In German, “vollkommen” is relevant to “Verkollkommnung”. In French, “roman” is relevant to “romantique”.
After an initial word is input, a user may usually desire to input a related word with a fast method. However, the conventional input method fails to meet the requirement. The user has to spell a complete word, which is time-consuming and laborious. For example, after “consume” is inputted, the user cannot input its noun form “consumption” fast.
Some software keyboard and input method may provide a word prediction function. For example, when the user input a word “won”, the software keyboard and input method can predict that the user may desire to input the contents “won”, “wonder”, etc., and indicate the user by providing these predicted words as candidate inputs for user selection. In traditional input methods, the word “wonderful” relating to “wonder” may be the word that the user desires to input, however, the word “wonderful” cannot be displayed as a candidate word due to various condition restrictions. Thus, if the user desires to input “wonderful”, the user has to further input more information to help the text input program or device filter other candidate words, so that “wonderful” may meet the requirement for being displayed as a candidate word. Accordingly, the input efficiency is impaired.